The Research Of Secure Application Protocol Based On Fog Computing For VANETs

With the development of vehicular ad hoc networks(VANETs)technology,vehic-ular users can enjoy more internet services while driving,such as downloading various multimedia files,and parking reservation,etc.Due to the continuous development of VANETs technology and people want to get more media services during driving,the amount of communication data exploded.Then it is difficult for the traditional cloud computing technology to dispose such mass data in real time.To make up for this issue,fog computing is proposed.Since the low latency and real-time interactive features of fog computing,it brings a new solution to deal with the big data in internet service applications.However,because fog computing is always deployed near the network infrastructures,the application is faced with many security threats,such as privacy challenges,fake messages attacks from the network infrastructures and nearby vehicles.Therefore,how to design a secure communication scheme to ensure the privacy-preserving and security of entities in VANETs based on fog computing has become the current research focus.In this paper,through the analysis of two different application scenarios in VANETs based on fog computing(i.e.,cooperative downloading and smart parking),two schemes about how to ensure secure communication in VANETs based on fog computing are pro-posed.These two schemes meets the security and privacy-preserving.The main works of this paper come as follows:1.Secure,Robust and Flexible Cooperative Downloading Scheme based on Fog Computing for Highway VANETs· The existing security challenges and application requirements of cooperative downloading based on fog computing in VANETs is summarized.Existing cooperative downloading schemes face the challenges of selecting most re-liable proxy vehicles,allowing flexible data downloading and authenticating the order of the file blocks/assisting vehicles.· To solve the above issues,a secure,robust and flexible cooperative down-loading scheme using our reputation based selection mechanism and ordered signatures is proposed.The vehicles in our cooperative downloading scheme are divided into client,proxy and assisting vehicles.A client vehicle is the initiator of a cooperative downloading task.A file requested by the client ve-hicle will be downloaded from a FS with the help of proxy vehicles that will forward the file to the client vehicle with the help of assisting vehicles.Using the reputation based selection mechanism,only vehicles with the highest ex-pected downloading capacities will be selected as proxy vehicles.This helps us to avoid selecting less reliable proxy vehicles.The flexible data download-ing is achieved by dividing a file into small blocks so that a proxy vehicle can flexibly vary the file / data download,for example based on existing condi-tion.Our scheme also achieves strong security,in the sense that it realizes tra-ditional authentication,privacy preservation and message confidentiality,as well as a newly introduced security requirement(i.e.,process authentication:authenticates the order of file blocks and the order of the assisting vehicles using ordered signatures).2.Secure and Reliable Parking Scheme based on Fog Computing for VANETs· The existing security challenges and application requirements of smart park-ing based on fog computing for VANETs is summarized.The existing scheme has the problem of multi-reservation attack,that is,vehicles reserve multiple parking spots for their own interests at the same time,which will lead to un-fairness and waste of resources.There are also secure issues such as some vehicles maliciously occupy the parking spots without reservations and dis-honest parking lots claiming they have more empty parking spots.· To solve the above issues,based on fog computing,a secure and reliable smart parking protocol using blockchains and linkable group signatures is proposed.It not only realizes traditional authentication,privacy preservation and mes-sage confidentiality requirements but also prevents multi-reservation attack.And we use two types of blockchains to prevent the dishonest parking lots that claim more empty spots than they actually have.Also,based on blockchains,we proposed a solution to detect if there is a malicious vehicle occupies a parking spot without reservation.